[media] tea6415c: return -EIO if i2c_check_functionality fails

If the adapter does not support I2C_FUNC_SMBUS_WRITE_BYTE,
return -EIO instead of 0.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/tea6415c.c

@@ -148,7 +148,7 @@ static int tea6415c_probe(struct i2c_client *client,
 
 	/* let's see whether this adapter can support what we need */
 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WRITE_BYTE))
-		return 0;
+		return -EIO;
 
 	v4l_info(client, "chip found @ 0x%x (%s)\n",
 			client->addr << 1, client->adapter->name);